Heat and Mass Transfer The unit of overall coefficient of heat transfer is kcal/m² hr °C kcal/m² kcal/hr °C kcal/m hr °C kcal/m² hr °C kcal/m² kcal/hr °C kcal/m hr °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred by molecular collision, it is referred to as heat transfer by Scattering Radiation Convection Conduction Scattering Radiation Convection Conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law. Directly proportional to Equal to None of these Inversely proportional to Directly proportional to Equal to None of these Inversely proportional to ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) P= 1, T = 0 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 0 P = 0, x = 1 and a = 0 P= 1, T = 0 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 0 P = 0, x = 1 and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be opaque when P=1, x = 0 and a = 0 P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 P=1, x = 0 and a = 0 P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 X = 0, a + p = 1 ANSWER DOWNLOAD EXAMIANS APP